Polymer 2.0 paper-input with firebase-document deletes data

[christophe-g]

With Polymer 2.0, firebase-document used together with paper-input as below:

<firebase-document path="/myPath" data= "{{data}}"></firebase-document>
<paper-input label="label" value="{{data.WILL_BE_DELETED}}"></paper-input>

deletes data on firebase.

This is posted for info (and warning) as the real culprit is iron-input as reported here: https://github.com/PolymerElements/iron-input/issues/143